This is a sprawling epic of a story, as the Doctor essentially takes on 'Death' (or the Kotturuh, the race who represent the concept of 'Death' as a being in the Whoniverse).

An exciting story from start to finish. Brian The Ood is a highly entertaining side character, and it's nice to see the Time Lord Victorious stuff from The Waters Of Mars expanded upon.

The cliffhanger is also a nice tease for the second book. I'm not sure if it was deliberate, but it felt reminiscent of the old RTD cliffhangers that would lead into the Christmas Specials.